Stabilized germicidal soaps and process of making the same



W. soaps have to be marketed at a price ditferential pared toordinarysoaps.

"STABIIVJVIIZEID GERMI'CIDAL som'mnimbcnss 1 OF MAKING THE SAME SeymoreGoldwasser, Teaneck, NJ., assignorto Lever Brothers Company, New York,N.Y., a corporation of Maine No Drawing. Application September 28, 1955Serial No. 537,301

16 Claims. (Cl.. 252107) This: invention relates to a process for thepreparation of germicidal detergents and to germicidal detergentsobtained by this process and more particularly to detergent compositionswhich combine the detergent properties of ordinary soaps and nonsoapdetergents" with the germicidal properties of N-substitut'ed thiuramsulfides, and to a process of preparing such detergents.

The normal. human skin is the habitat of millions ofa bacteria, themajority-of which are beneath the surface of the skin. Of the fortymillion bacteria usually found .on and in the skin of the two hands andarms to the elbows, only about one million arevtransients residing onthe skin surface; the remainder areresident bacteria and 1 resideiii-subsurface skin layers. Transient bacteria are readily removedmechanically hy ordinary soap. Resident bacteria are usually removedonly following attack by a satisfactory degerming agent, whoseeffectiveness is due to its absorption by the skin, so that it isavailable "to act continuously on bacteria present in the subsurfacelayers, thereby preventing their multiplication to any appreciabledegree. 7

It is for this reason that germicidal'soaps which have eagerness ray,17-, 19 0 2 view of the very considerable research which led'to thedevelopment of these compounds, the discovery of another germicide whichcould be combined soap would be quite unexpected. V

In accordance with. the instant invention, a germicidal detergent soapis provided comprising as a germicidal agent a thiuram sulfide havingeach thiuram nitrogen atom fully substituted with aliphatic groups, anda peroxide which acts as a stabilizer for the thiuram sulfide. I

At concentrations appreciably less than would be used in the case ofhexachlorophene (2',2 '-dihydroxy-3,5, 6-

3,5',6-hexachloro diphenyl methane); suchthiuram sulfides are capable ofproducing germicidally potent soap compositions. V

The compositions of the invention are more active against gram-negativeorganisms such as Escherichia coli than hexachlorophene soaps and aremore substantive to the skin than hexachlorophene soaps. The soaps ofthe invention lack otfensive'odors. The low cost and availability ofthese thiuram sulfides favorably distinguish them from other germicides.

The term thiuram sulfide is inclusive of thiuram monosulfides,disulfides, trisuliides, tetrasulfides and hexasulfides.

The aliphatic thiuram sulfides used as a germicidal' agent in the soapcompositions of the invention have the,

following formula:

a t-W1 v 1 s s n has the value of one to six, and Z and Z each areselected. from the group consisting of a single bivalent cycloaliphaticradical and two monovalent aliphatic radicals. The number of carbonatoms is not critical, but

the antibacterial activity tends to decrease as the number recently beenplaced on themarketj-havev found a wide application. Such soaps containa'small amount of a germicidal agent and the use of the soap in dailywashings provides suflicient germicide to keep the bacterial count. ..ata practical minimum. In fact, the'bacterial Y 1 count can be lowered toa point at which it equals or "is even lower than that produced-by thesurgeon through 't'hei'application of the standard 'hospitalnscrub-uptechm ae; "Hexachlorophene: r: (-2,2'-.- dihydroxy,-.3,5,6-3',5,6T-

1 hexachlorodiphenylv methane) has been proposed .for. I use in} soap.Thissubstance, however, in common with other 2,2="-dihydroxyhalogenateddiphenyl methanes, has a low potency 'atullow'concentrations. It: not very elfective againstgrant-negative organismssuch as Escherichia coli.

Soaps containing hexachlorophene tend to darken in daylight, and mayhave or. develop an 'objectionableodor which lessens the attractiveness.of such soaps to the consumer. Moreover; 2;2-:dihydroxy halogenateddiphenyl methanes are expensive chemicals, and since fairlyrlargeamountsl tox3-% basisfsoap weight) are needed for eli -ec'tivegermicidal action, hexachlorophene germicidal 00111 thes,-.various--phenolic materials have'been combined ap;- but because ofthe generally recognizedtde action of. soapupon the bactericidal.properties- 5 5 gerr'nici'rlal agents, germicidal soapsj -have not; beenstaine V by Kunz and Gump and is reviewed in some detail at columns 3'and 4 of their US. Patent No. 2,535,077,

. dated December 26,- 195 0; Althoughfthe 2 ;2f-'d'iliydroxy ha'lena'ted diphenyl"methanes iare'wantingfin some r sp'e they have" beenrecorded-as" unique in that their inaddition to -the=2;2"-dihydroxy'halogenated diphenyl This point-hasbeen etfectively demonstrated Ifgiirrhicidal potency is relatively'jiinaifected by soap. In I of carbonatoms increases, and therefore Z and pref erably have from two to eightcarbon atoms.

When 2, and/ or Z are bivalent, taken with the thiuram nitrogen atomthey form a saturated or unsaturate d heterocyclic ring in which thethiuram nitrogen atoinzis 1 p A typical heterocyclic radical of one ofthe ring atoms. this type is piperidine.

'When Z 'and/or Z are monovalent they can be selected from the groupconsisting of saturated and unsaturated straight and branchedchainfaliphatic radicals, preferably having from one to four carbonatoms.

Among those which can be employed areiethyl, methyl, 1

propyl, isopropyl, n-butyl, isobut-yl,v tert.-butyl, sec.-butyl,

butadiene, butylene and propylene. Alkyl radicals hav- 5 ing from one totwo carbon atoms are preferred;

Typical aliphatic thiurammonosulfide's {coming within the invention are:

effectively with Typical aliphatic thiuram disulfides coming within theinvention are:

A typical thiurarn tetrasulfide coming within the invention is:

The aliphatic thiuram'sulfides are known classes of materials, andtheirpreparation is set forth in the literature. Forthemost part they areinsoluble in water, soluble in alcohol, acetone and benzene, and verysoluble in chloroform and carbon disulfide. In the quantities in whichthey are employed in soaps,.they do not produce skin irritation, are nottoxic, and are compatible with the usual soap components, includingneutral salts, perfume, opacifiers and small amounts of carbonates.

The term soap as used herein refers to alkali metal soaps of thesaturated and unsaturated higher fatty acids having from' about eight toabout twenty-six carbon atoms, such as. capric, caprylic, lauric,myristic, palmitic, stearic, oleic, linoleic, linolenic, arachidic,behenic, margaric, tridechoic, and cerotic acids and themixtures of suchacids naturally occurring infats, oils, waxes, and rosins, such as thesoaps of coconut oil fatty acids,,ta1low fatty acids, pig fat, fish oilfatty acids, beeswax, palm oil fatty acids, sesame .oil fatty acids,peanut oil fatty acids, olive oil fatty acids, palm kernel oil 'fattyacids, cottonseed oiliatty'acids, soyabean oil fatty acids, corn oilfatty acids, bab,assu oil fatty acids, rosin acids, abietic acid, andgreases,

Only small amounts of thiuram sulfide are required to render soapgermicidaL; -An amount as low as 0.01% based on the weightof the soapproduces a soap composi tion having excellent antibacterial potency. Asmuch as 5% has been used to advantage. There is no need to to thethiuram sulfide.

. which the soap is formed, e.g.,

employ more than is required to give'the desired germicidal eifect, andin general for this reason from 0.2 to

2.0% would :be. preferred. Increasing the concentration of thiuramsulfide beyond 5% further increases the costof the soap and might tendto reduce the detergent properties of the composition. 'At unnecessarilyhigh concentrations there is a possibility of skin irritation due Itwill readily be seen that the thiuram sulfide concentrationnot criticalbut would be determined from a consideration of these factors, as

long as enough is used to give the desired antibacterial effect;

When exposed to high temperatures for long periods of time or over longperiods of storage even at ordinary temperatures thiuram sulfide in asoap composition shows a tendency'to decompose. The decompositionproducts are unknown but appear to include complex sulfur compounds,amines, carbon disulfide, and mercaptans. These materials lead to thedevelopment of an undesirable and in some cases an exceedinglyunpleasant odor. Reactive sulfur-bearing compounds appear also to beavailable, because if a soapcontaining the decomposition products ofthiuram disulfide comes into contact with copper ion 'a dark coloredsulfur compound of copper is formed, insoluble in Water, resulting in adarkv colored stain Which can be removed by customary cleaning methodsor by treatment with acid but Which it is desirable to avoid ifpossible. In accordance with the invention, therefore, there isincorporated in the thiuram sulfide soap composition aperoxide whichactsas an inhibitor against the {*decomposition ofthe thiuram sulfide.

' I The term peroxide is inclusive of any organic or inorganic compoundwhich forms hydrogen peroxide in alkaline solution, for example, sodiumperboate, sodium pyrophosphate peroxide, v'lauroyl peroxide, benzoylperox- ..-ide, and sodium persulfate.

The organic peroxides are preferred'because they leave no salt residueupon decomposition. A

. In general, it can be said that any amount of the peroxide Willimprove the stability of the thiuram sulfide soap against odor andstaining, and the amount which would be employed therefore will dependupon the storage stability which is required. It may be observed that inthe cases where the soap, because of prior processingr'nethods',contains reducingagents, for example, hydrosulfit'e added inthe kettle to bleach {the soap, it is neces- ;sary to employ asupplemental amount or the peroxide to function as an oxidizing agent todestroy such reducing agents.

There is no upper limit to the .amouritotperoxide j which can be used.Amounts within the range of 0.05 to' 2% have been found to give adequateinhibition of odor formation and staining, but as much as 5% is notdisad- "vantageous, although usually unnecessary and therefore noteconomical. Even more than 5% can be. used.

It has been found that free alkali must be eliminated from the thiuramsulfide-peroxide-soap composition. This may be accomplished, if theperoxide is acidic, by addition of a sufficient additional amount of theperoxide where necessaryto take up all of the free alkali. If theperoxide is notacidic, then free acid is added in the amount required totake up allof the free alkali. As the acid, there can be used an.inorganic acid, such as boric acid, or an acidic inorganic salt, such,as sodium bicarbonate, or an organic acid, including the long and shortchain aliphatic acids, especially the free soap. acids of stearic,myristic, and palmitic'acids, or mixtures of any of these. i

When aperoxide is incorporated in these soap compositions, it isimportant that all of the ingredients be added before the thiuramsulfide, and that the thiuram sulfide be thoroughly dispersed in thesoap mixture. Mixing of the batch should not be continued beyond thepoint at which the thiuram sulfide is thoroughly dispersed. I

While several mixing; procedures will be apparent mi those skilled inthe art in order to achieve thisrc sult, the

following procedureis-recommended: T he soap chips are weighed into themixer and fol-lowed immediately by addition of the peroxide. Theperoxidecansbeadded in the form of a solution 'or dispersion in water,= irrwhich the concentration of the peroxide is not critical,- 1 'MlXlIlgis continued for a sufiicient time to insurethorou'gh" dispersion. of.the peroxide in'the soap. The remaining components of the mix, forexample, perfume and dye, are added, in the form of. a solutionif.desired, as quickly as possible and mixing is continuedagain fora longenough period to insure a thorough dispersion. Thereafter the thiuramsulfide is added with. complete and'adequ'ate mixing only for the timetoinsure uniformity? of .disper- The final mix then' can be treatedin themaven--- sion. tional ways to produce the desired soap. To. form a bar,for example,- the mix can be plodded and extruded using conventionalequipment.

The thiuram sulfide soaps in accordance with the in v I vent-ion can beformed-as bar soaps, powered soaps, chip; soaps, flake soaps, beadsoaps, bar andcakesoaps and soap compositions intended for toilet,washing'an'd disinfectant purposes in addition to their use asdetergents.

The compositions canbe dried in. any desired way;-spray drying isconvenient in many instances. It is desirable to hold the temperature towhich the .mix is-subjected during conversion intoits final formbelowthe tempera ture at which the thiuram sulfide would be decomposed.Soap mixtures'in accordance with the invention have been subjected totemperatures up to-'I25' F. for'periodsof up to one hour withoutdisadvantage. V

The germicidal effectiveness of the soap compositions of the inventionhas been measured by theSerial Basin iv dividual subjects are used as apanel in each test. Two types of soap are usedin the test, thegermicidal soap employed daily for the two Week test period andthe plainsoap used where the wash water is collected in various basins fordetermining the counts of bacteria removed;

The subject exposes the armsuptotheelbow, and 2000 cc. oflukewarm tapwater are run into the sterilized first i p basin, the bacterialcount-of the water .beingdetermined I byre'moving two lj'cc. samples'which ar'e adde 18cc. oflnutrient" a ar; subject mo upto the wristline,thenapplies plain: soap for 'fifteen'secg g' 1 ends followed by thoroughlatheringfor sixty's'econdsk The. hands are rinsed thoroughly the basin.1

Two more similar washings are carried out successively under the tap,the area. covered extending almost to the elbows, and the Water isdiscarded.

The subject then moves to the second basin containing 2000 cc. oflukewarm tap water and carries out the washing procedure exactly as inthe first basin. i i

for fifteen. seconds into The subject then moves to the third basin'andrepeats Y V the washing procedure of Basins 1 and 2.

Two 1 cc. of samples of 2000 cc. wash water each 4 basin are removedusing 'a sterile pipette'and added'to 15 cc. of nutrient agar in sterilePetri dishes. This is agitated, allowed to cool and harden and incubateat 37 C. for forty-eight hours. At the end of this time'the nuni= i berof colonies present are counted and the.counts multiplied by 2000.

The above test is repeated at intervals over the two weeks test period.The percent reduction 1 in bacterial count is computedon the basis ofthe reduction in count of the 2nd and 3rd, basin wash waters.

(2) The Zone Reduction Test.-This test measures the inhibitory eifect ofan 8% solution within the zone of direct contact of the solution withthe bacteriaseeded agar. A range of dilutions is investigated todetermine the minimum concentration of germicide in the soap solutionrequired to effect a strong reduction in the bacterial count in the agarin direct contact therewith. An 8% 1 solution of the soap is used sincethis is approximately the concentration of soap found in lather.

. For use in the test, cultures of Staphylococcus aureus and Escherichiacoli are maintained on nutrient broth with transfers made daily. Inpreparing the agar plates, 0.1 ml. of a twenty-four hour nutrient brothculture of the test organism is mixed thoroughly into 15 ml. of meltednutrient agar, which is then poured into a Petri plate and permitted toharden.

Filter paper discs (0.5 inch in diameter) prepared from Whatman FilterPaper No. 2 are placed on the hardened agar circularly (about 0.75 inchfrom the periphery).

Each disc is wetted carefully with one measured drop of the 8% solutionof a test soap, using a syringe (25 gauge needle). Six or seven discscan be arranged on each seeded agar plate, including the control plainsoap. Duplicate plates are prepared and are incubated for twenty-four toforty-eight hours at 37 C.

In counting the plates, the filter discs are carefully removed withforceps and the zones of disc contact are examined microscopically(100x) with replicate counts made of fields selected at random. Tofacilitate counting, a Howard Micrometer Disc (No. 823) can be insertedinto the ocular piece (10X); five fields of three adjacent squares arecounted and the average field count determined.

The antibacterial potency of a test soap solution is expressed in termsof a Bacteriostatic Index which is computed from the average zonereadings as follows:

Bacteriostatic index Av. zone count of test soap X100 Av. zone count ofcontrol soap Index:

8S-no antibacterial activity 60-85slight 30-60-moderate 30--strong--very strong 1 Basis soap weight.

for fifteen minutes. At the end of this time, the soap solutions aredrained from the discs and sterile water added. The discs in the sterilewater are shaken for fifteen minutes with a frequent change of water andthen placed on the inoculated agar as in the Zone Reduction Test.

The compositions prepared in accordance with the invention have shownexcellent germicidal effectiveness when subjected to these tests.

The following example illustrates the invention:

Soap chips (750 lbs.), formed from a charge of tallow and 20% coconutoil, bleached by the addition of sodium hydrosulfite Na S O andcontaining 0.05% free alkali, were weighed into the mixer, followingwhich 1 lb. 8 oz. of lauroyl peroxide was added at once. Mixing wascontinued for five minutes after which 5 lbs. 13 oz. of perfume and dyewere added over a period of one minute and mixing continued for threeminutes. Tetramethyl thiuram disulfide (7 lbs. 11 oz.) was added byspreading it over the surface of the mix and mixing was continued fornot more than four minutes. At the end of this time the tetramethylthiuram disulfide was found to be thoroughly dispersed in the soap. Themix was transferred to a refiner where it was extruded through screensinto another extruder and then into a plodder and formed into bars, allat temperatures between and F.

Any of the above-mentioned thiuram sulfides and/or peroxides can besubstituted for the tetramethyl thiuram disulfide and lauroyl peroxidewith satisfactory results.

The soap bars obtained were packed in an inner wrap of glassine paperand an outer carton of white patent coated board and subjected tostorage at ordinary room temperatures for nine months. No change in theproduct was noted, whereas in the case of a soap containing thiuramsulfide but no lauroyl peroxide prepared exactly as set forth, yellowingof both the glassine and the board was observed, due probably to sulfurcompounds formed by decomposition of the tetramethyl thiuram disulfide.The aged product containing the lauroyl peroxide had no odor and did notproduce stains in the presence of copper ion, whereas the product whichdid not contain the lauroyl peroxide did produce such stains and had astrong odor.

It has been postulated that the decomposition of the thiuram sulfidewhich leads to the difliculties noted above follows the followingcourse:

The carbon disulfide, .dimethylamine and other decomposition productsofdithiocarbamate, would be responsible for an ofi odor in the product.

A reducing agent such as hydrosulfite or sulfite might react in asimilar fashion:

9 a t I From'Equation it can beseen thatbnemoIecuIe of hydrosulfite canbe responsible for thdecompositiohto the ditliiocarbamate state of threemolecules of tetramethyl thiuram disulfide and that thedeoomposition isi very sensitive to hydroxyl ion.

, any aqueous solution in the presence of a reducing agent.

"(Germs or bacteria may act as reducing agents.) In use it is not clearWhether the-germicidal properties of the soap" are 'due to the thiuramsulfide or to the dithiocarbamate, but it is not important to establishthis since both' are present in soap solutions. Dithiocarbamate has beenfound to enjoy but a transitory existence in" soap compositions, andthereforein order to preserve its activity in soap solutions which aresubsequentlypr'e- I pared from the compositions, should it be thegermicidal agent in thelsoap solution as used, the thiuram sulfide iskept from forming the dithiocarbamate in the soap,

but not in the solution, by the'peroxide of. the invention.

, t The free alk ali is determined in accordance with the followingprocedure: The soap, befor'e' addition of dye, thiuram sulfide andstabilizing-agent, is weighed outin a 250ml. extraction flask on atriplebeam or torsion balance, 12.4 gms. in the case of soap chips or finesoap, i.e., soaps of higher fatty acids, 31 gms. in the case of framedsoaps and pan samples, i.e., soaps of about 63% fatty acids. To the soapis added approximately 100 ml. of neutralized alcohol and several glassbeads and the soap is dissolved completely in'the alcohol by boilinggently on a hot plate under a reflux air condenser. One ml. ofphenolphthalein indicator is added and the solution titrated while hotto the disappearance of the phenolphthalein color. N/4 solutions areused for framed soaps and pan samples, and N/ solutions for soap chipsand hue soaps. The color change is not very defiinitc for the latter andis recognized in a change of color rather than a disappearance. A blankdetermination is made on 100 ml. of the neutralized alcoholcfor eachbatch when N/10 solutions are used, and the volumes of acid or alkalirequired for neutralization are noted. The calculation then is carriedout according to the following equations: For soap chips and fine soaps:I v Ml. N/lO acid correctedlx 0.0031 x 1.00 a 12.4

=percent; Na O Ml. N/10 aoid 0.025=percent Na i) For framed soapsand pansamples: Ml. N/4 acidX 0.00775 10o 31 i =percent N320 Ml. N /4 acid0.025=percent Na O The compositions of the invention meet all ofthererecommended for uses in which both detergent and degermingcharacteristics are desired. The test results show that the compositionsused routinely for a period of from one to two weeks lower the bacterialflora of the skin to, a very low level, equivalent to that obtainable bymeans of the standard hospital scrub-up operation. The compositions areparticularly valuable for routine surgical and hospital use andgenerally useful in the prevention of infections arising from skinbacteria.

Those skilled in the art will perceive manyvariations 7 in thecompositions of the invention. For example, the

aliphatic thiuram sulfide need not be the only germicidal compositionagainst decomposition of thiuram'sulfide as evidenced bythe developmentof odor andstaining. charagent; other germicides, such as ,2',2' -diliydroxy"halo genated "diphe'nyl methanes, can be included, for ample, ifdesired. The soap compositions, in addition to the soapand germicide,will also usually contain fillers; coloringmaterials and perfumes, asdesired, as is familiar to-those skilled in the art. V r

The compositions containing the thiuram sulfidejmay contain mixtures ofdetergents, such as soap andah' anionic nonsoap, or soap and a nonionicnonsoap. Typical satisfactory anionic nonsoaps are the alkyl sulfates,

typified by sodium lauryl sulfate, known in the trade as Duponol C, thealkyl aryl' sulfonates, typified bythe sodium polypropylene benzene ort'oluene sulfonates', and the sodium keryl benzene or toluenesulfonates, the sulfated ethoxynated phenols, typifiedbythejamnioniumsalt of sulfated ethoxynatednonyl phenol; prepared by a condensation ofnonyl phenol with live moles ofethylene oxide, and the sodium fatty acidesters of taun'ne,typitied by sodium palmiti'c or oleic' methyltaurideor mixtures thereof, and the esters of higher" fatty acids and hydroxyethane 'sulfonates such' as oleic acid: ester of hydroxy ethane sodiumsulfonate. Also useful'are nonionic nonsoaps, such, asthe"'polyethylene, glycol esters of thehigher fattyacids, typifiedbypo'lyoxyethylene ethylene'tand propylene glycol ste'arates, thepolyethylene glycol ethers of alkyl phenols, typified by thecondensation product of octyl and nonyl phenol with five, to twelvemoles of ethyleneoxide; and the higher fatty acid esters ofsorbitan-ethylene oxide condensates, such as s'orbitanmonostearate esterofjpolyoxyethylene glycol. Theymay bein any of the-forms described heretofore, including cakes or powders, and may include various fillers,sudsing agents and ingredients conventionally employed in detergentformulations, They may be compounded for various purposes, such as forshampoo, dishwashing, textile laundering, toilet soap and similarpreparations.

The thiuram sulfide may be included in compositions which contain soapor other surface active agents not intended primarily for detergent use,suc h' as various.

powdered cosmetics.

All percentages in the specification and claims are by weight of thesoap.

This application is a continuation-in-part of-application Serial No.397,001, filed Decemberf 8,1953, nowv abandoned. 1 p I claim: 1. Agermicidal detergent composition amount of a thiuram sulfide having theformula:, T

r el- 2 S S a where n is an integer from one to six and Z and Z arehydrocarbon radicals having from two to eight carbon atoms and areselected from the group consisting of a single bivalent cycloaliphaticradical and two monovalent aliphatic radicals, and a peroxidecharacterized by forming hydrogen peroxide in alkaline aqueous solution,said i peroxide being in an amount to stabilize'the detergentacteristics.

2. A germicidal detergent soap comprising soap suba stantially free fromfree alkali, a peroxide characterized a by forming hydrogen peroxide inalkaline aqueous solustantially free from free alkali, a peroxidecharacterized '7 substantially free from tree alkali comprising soap; agermicidal f 11 by forming hydrogen peroxide in alkaline aqueoussolution, and a germicidal amount of N-tetramethyl thiuram monosulfidesaid peroxide being in an amount to stabilize the detergent compositionagainst decomposition of ,thiuram sulfide as evidenced by thedevelopment of odor and staining characteristics.

4. A germicidal detergent soap comprising soap substantially free fromfree alkali, a peroxide characterized by forming hydrogen peroxide inalkaline aqueous solution, and a germicidal amount of N-tetramethylthiuram disulfide said peroxide being in an amount to stabilize thedetergent composition against decomposition of thiuram sulfide asevidenced by the development of odor and staining characteristics.

5. A germicidal detergent composition in accordance with claim 1 inwhich the thiuram sulfide is present in an amount within the range from0.01 to about 5%.

6. A germicidal detergent composition in accordance with claim 1 inwhich n has the value of one.

7. A germicidal detergent composition in accordance with claim 1 inwhich n has the value of two.

8. A germicidal detergent composition in accordance with claim 1 inwhich the peroxide is lauroyl peroxide.

9. A germicidal detergent composition in accordance with claim 1 inwhich the peroxide is benzoyl peroxide.

10. A process of forming a germicidal detergent composition comprisingdispersing in soapa peroxide characterized by forming hydrogen peroxidein alkaline aqueous solution, said peroxide being in an amount tostabilize the detergent composition against decomposition of thiuramsulfide as evidenced by the development of odor and stainingcharacteristics, and then dispersing therein a germicidal amount of athiuram sulfide having a formula:

where n' is an integer from one to six and Z and Z; are hydrocarbonradicals having from two to eight carbon atoms and are selected from thegroup consisting of a single bivalent cycloaliphatic radical and twomonovalent aliphatic radicals, including adding an acidic compound ifnecessary to eliminate free alkali and form a composition substantiallyfree from free alkali.

11. A process in'accordance with claim 10 in which the peroxide isacid-reacting, and is added in an amount to eliminate free alkali in thefinal composition.

12. A process in accordance with claim 10 in which the acid-reactingcompound is an inorganic acid.

13. A process in accordance with claim 10 in which the acid-reactingcompound is an inorganic acid-reacting salt.

14. A process in accordance with claim 10 in the acid-reacting compoundis an organic acid.

15. A process in accordance with claim 10 in which the peroxide islauroyl peroxide.

16. A process in accordance with claim 10 in which the peroxide isbenzoyl peroxide.

which References Cited in the file of this patent UNITED STATES PATENTSRe. 22,750 Tisdale et al. Apr. 30, 1946 1,278,518 Tanaka Sept. 10, 19181,791,876 Somerville Feb. 10, 1931 1,824,809 Flammer et a1. Sept. 29,1931 2,695,881 Elliott et a1. Nov. 30, 1954 OTHER REFERENCES BritishMedical Journal, June 17, 1944, article by Gordon et al., pp. 803-806.

1. A GERMICIDAL DETERGENT COMPOSITION SUBSTANTIALLY FREE FROM FREEALKALI COMPRISING SOAP, A GERMICIDAL AMOUNT OF A THIURAM SULFIDE HAVINGTHE FORMULA: